Manatee Traveler in Northeastern Waters Not Chessie

USGS Manatee Expert Cathy Beck on Photo-cataloging Manatees:

Manatee with old boat propeller scars that biologists use to identify this individual. USGS. [larger version]

"To initially document a manatee, the animal must have healed and unique features, and the entire dorsal and lateral aspects of the body and tail must
be photographically documented. That first step gets the manatee into the Manatee Individual Photo-identification System (MIPS) database as an individual, but then resightings with photo-documentation of the manatee's features are necessary because manatees often acquire new scars and (or) mutilations that can change an individual's appearance. To match a manatee to a known individual in the MIPS database, we need a good photo of a feature and its exact position on the body or tail. The manatee photographed this summer in Rhode Island has tail mutilations that do not match the tail mutilations on Chessie and, unfortunately, do not match the tail mutilations on any manatee currently in the MIPS database."

A West Indian manatee was sighted in various waters of the northeastern United States during July and August 2006. It traveled up the Hudson River into Harlem, visited Cape Cod, Mass., and, on August 20, was sighted in Bristol Harbor, R.I.

The question on everyone's mind was: Is it Chessie on summer vacation? The manatee now known as Chessie first gained notoriety in fall 1994, when he was sighted in Chesapeake Bay, Md., far beyond the usual range of manatees in the southeastern United States. Captured and returned by U.S. Coast Guard plane to Florida, Chessie was subsequently radio tagged and tracked by the U.S. Geological Survey (USGS)'s Sirenia Project. He gained new fame in summer 1995 by swimming past the mid-Atlantic States, through New York City, all the way to Rhode Island, farther than any manatee had been known to venture. He was sighted in Virginia in 1996 and 2001.

This summer's traveler is a new manatee, not Chessie, as determined by USGS manatee researchers and announced on August 23, 2006. The roving manatee's identity is still unknown. Video footage of the manatee was sent to USGS researchers in Florida, who used a manatee-photo-identification catalogcalled the Manatee Individual Photo-identification System, or MIPSto compare scar patterns on the animal with others in the database. Photographs of the mystery manatee do not match those of Chessie, nor of any other Florida manatees that have been documented for the MIPS database.

In 1994, scientists photographed Chessieand his unique markings and scarsduring his rescue from Chesapeake Bay. Chessie has a distinctive long gray scar on his back, with several small white spots apparent within the scar.

Above: Portrait of a manatee (neither Chessie nor the manatee sighted in the Northeast in summer 2006). USGS. [larger version]

Above: Photograph of Chessie taken in 2001 shows a distinctive white scar used to identify him. USGS. [larger version]

"Since then, Chessie also has acquired tail mutilations, but these are not severe," said Cathy Beck, a biologist with the USGS Sirenia Project. "Reports of manatee sightings far from the usual summer range are of great interest, and we appreciate receiving photographs to help us document the individual whenever possible," Beck said.

The new far-traveled manatee still had time to reach Florida waters before the onset of cooler weather. USGS manatee scientists believe that Chessie's migration from Florida to the Chesapeake Bay may have been common for manatees in previous centuries. The repeated sightings of a "sea monster" in the Chesapeake Bay, nicknamed "Chessie," date back throughout the 1900s and may include manatee sightings that were not properly identified. Chessie was named after the purported sea monster.

"Cooperation among members of marine-mammal-sighting networks, Government agencies, and the public on tracking Chessie's migration has raised the public's awareness of this unique endangered marine mammal," said Jim Reid, a biologist with the USGS Sirenia Project. "Manatees are long-lived and typically repeat established movement patterns. It's likely that sightings of Chessie or other manatees will occur again in these northern areas."